1. Field of the Invention
The present invention relates to a liquid crystal display apparatus that displays video using a corrected video signal.
2. Description of the Related Art
As a display element used in a video displaying device, an active type liquid crystal display element in which a liquid crystal layer is installed through an alignment film between a semiconductor driving element substrate and a transparent electrode substrate is disclosed (see Japanese Unexamined Patent Application Publication No. H07-301778). The semiconductor driving element substrate is the semiconductor substrate on which a driving element for driving a circuit and pixel electrode and the like are installed. Meanwhile, the transparent electrode substrate is a transparent electrode on which the transparent electrode or the like is installed. Alignment film is intended to align the liquid crystal molecules in a predetermined aligning state.
In the liquid crystal display element, when a voltage is applied between the pixel electrode and the transparent electrode, alignment state of the liquid crystal molecules is changed according to the potential difference between the electrodes, and the optical properties of a liquid crystal layer is also changed accompanying with the change in the alignment state. Since optical modulation can hereby be performed using changes of the optical properties of the liquid crystal layer, video can be displayed using the liquid crystal display element.
Among the liquid crystal display elements, especially a liquid crystal display element, which utilizes a liquid crystal having a vertical alignment property (so-called vertical alignment liquid crystal) has a high contrast and a rapid response speed, it is noted that display capability can be improved. In a case where the vertical alignment liquid crystal is used, since liquid crystal molecules are aligned vertically to the substrate surface of the semiconductor driving element substrate when application voltage is zero, a display state of so-called normally black mode is obtained. Meanwhile, the liquid crystal molecules are inclined to the substrate surface, when voltage is applied, and optical transmittance is changed. Especially, in this case, if the inclination directions of the liquid crystal molecules at the time of inclination are not identical to each other, non-uniformity in the contrast occurs. Accordingly, in order not to cause non-uniformity in the contrast, it is necessary to align the liquid crystal molecules in a state inclined in advance at a slight angle (pre-tilt angle) in a certain direction.
As a method of aligning the vertical alignment liquid crystal in the desired alignment state, there is a method of using an organic alignment film represented by a polyimide, and a method of using an inorganic alignment film represented by a silicon oxide. The former is to control alignment state by rubbing the organic material film, and the latter is to control alignment state by obliquely depositing the inorganic material film. It is noted that the inorganic alignment film is capable of realizing further high luminance improvements in the display image.
Nowadays, in order to realize improvement in high luminance display images, the power of the light source becomes higher, and alignment film is likely exposed to the light with high intensity. For that reason, in view of ensuring the display capability of a projector over a long period, it is preferable to use an inorganic alignment film having a high light-resistance rather than an organic alignment film having a low light-resistance. In a case of using the inorganic alignment film, when the silicon oxide is obliquely deposited, it is possible to control the pre-tilt angle by changing the incidence angle of the deposited particle.